Promoter analysis of the Drosophila melanogaster gene encoding the pterin 4 alpha-carbinolamine dehydratase

Pterin-4 alpha -carbinolamine dehydratase (PCD) is a key enzyme in the rege neration pathway of tetrahydrobiopterin. Previously, we isolated and report ed the Drosophila melanogaster gene encoding PCD. In the present study, we isolated and characterized the Drosophila virilis gene encoding PCD. The Dr osophila virilis PCD gene has two introns and an open reading frame to enco de a protein of 101 amino acids. The amino acid sequence of Drosophila viri lis PCD shows a 83% homology to that of the Drosophila melanogaster PCD pro tein. From the alignment of the nucleotide sequence in the 5'-flanking regi on of the Drosophila melanogaster and Drosophila virilis PCD genes, we foun d four conserved sequences. Using a transient transfection assay, we showed that one of the conserved sequences (-127 similar to -115) is critical for expression, also the minimal promoter region between -127 and +51 is neces sary for the efficient expression of Drosophila melanogaster PCD.